Air humidifier devices



0a. 24, 1967 N. LAM 3,348,828 8 AIR HUMIDIFIER DEVICES Fil ed Jan, s,1966 8 Sheets-Sheet 1 INVENTOR Nikolaus Luing- ZWQ ATTORNEYS Oct. 24,1967 N. LAING 3,348,828 AIR HUMIDIFIER DEVICES Filed Jan. 5, 1966 8Sheets-Sheet 2 V ATTORNEYS Oct. 24, 1967 I LAlNG 3,348,828

AIR HUMIDIFIER DEVICES Filed Jan. 5, 1966 8 Sheets-Sheet 5 1 INV 0RNigsilgus L ning 32*, uaff% XMW ATTORNEYS Oct. 24, 1967 Filed Jan. 3,1966 N. LAING 3,348,828

AIR HUMI-DIFIER DEVICES 8 Sheets-Sheet 5 LNVENTOR NlkOlOUS Lulng I l W,a X/MM/I,

ATTORNEYS A} Oct. 24, 19-67 N. LAING 3,348,323

' AIR HUMIDIFIER DEVICES Filed Jan. 5, 1966 8 SheetsSheet 'v f IJQ /i?INVEN'IY'OR ATTORNEYS Filed Jan. 5, 1966 Ala HUMIDIFIER DEVICES 8Sheets-Sheet 8 I I I I I I I I I I I f I I I I I I I I I I I I I I I I II I f I I ATTORNEYS United States Patent 3,348,828 AIR HUMIDIFIERDEVICES Nikolaus Laing, 35 Hofener Weg, 714-1 Aldingen,

near Stuttgart, Germany Filed Jan. 3, 1966, Ser. No. 518,340 Claimspriority, application Austria, Aug. 6, 1965, A 7,305/65 16 Claims. (Cl.261-142) ABSTRACT (IF THE DISCLGSURE Air humidifying device having anair inlet and air outlet with a cross fiow type blower for moving airthrough the device and having a pump for moving water from a liquidreservoir into the path of the air fiow through the device.

This invention relates to means for humidifying the air by evaporationof water and this application is a continuation-in-part of my .priorapplication Ser. No. 221,621 filed Sept. 5, 1962, now Patent No. 2, 2,which is itself a continuation-in-part of application 6 1,- 114, filedJuly 5, 1957, the latter application being now abandoned.

The invention has for its main object to provide a compact, simple andefiicient form of air humidifying apparatus.

The invention makes use of a cross flow fian, herein defined as onecomprising a cylindrical bladed rotor mounted for rotation about itsaxis in a predetermined direction and defining an interior space, andguide means defining with the rotor an entry region and a dischargeregion, the guide means and rotor co-operating on rotation of the latterin said predetermined direction to induce a flow of air from the entryregion through the path of the rotating blades of the rotor to saidinterior space and thence again through the path of said rotating bladesto the discharge region. Preferably according to the invention the guidemeans and rotor co-operate to set up a vortex of Rankine characterhaving a core region eccentric of the rotor axis and a field regionwhich guides the fluid so that flow through the rotor is strongly curvedabout the vortex core.

The apparatus according to the invention comprises, in its broad aspect,a cross flow fan mounted within a housing and producing in operation aflow of air between an inlet and an outlet, and humidifying meansextending over the length of the rotor and parallel to the axis thereof,said humidifying means including elements to carry water into the pathof said flow and means to supply water to said elements. Thiscombination can be designed to combine a large effective area ofwater-carrying elements with a substantially even flow of air past oracross this area, thus simultaneously obtaining both a compactconstruction with operating efiiciency. The water carrying elements canmost effectively, compactly and cheaply be provided over a rectangulararea. The main types of prior art fan are axial and centrifugal. Theaxial fan produces a fiow which has essentially an annular crosssection, and is not therefore adapted to produce an even flow of airover a rectangle. The centrifugal fan is limited in that the rotorcannot usefully have a length exceeding 0.6 or 1.2 multiplied by itsdiameter, depending on whether air enters from one or both ends of therotor. Thus the area over which an even flow can be produced isrestricted: moreover the fan is bulky in relation to its throughput. Itwill be appreciated therefore that the invention provides a combinationcapable of advantages which could not be achieved with these prior artfans.

The water conducting elements may comprise a plubecome apparent from thefollowing rality of vertically suspended wire coils; in this case therotor is preferably also vertical, and can be of a considerable length.The humidifying means can alternatively be provided by fibrous material,Wod fibres for example, either'in the form of a readily air-permeablelarge-area filter or in a form such that the air flows over one side ofthe area. The water conducting elements can, if fibrous, take up waterby capillary action but in all cases it is preferred to have a watertank in said housing and a pump to circulate water from said tank in aclosed circuit including said water-carrying elements. The pump maycomprise an endless fibrous cord dipping into the tank and mounted onpulley wheels driven by said motor and including an upper wheel abovesaid tank, and means associated with the upper pulley wheel to collectwater raised from the tank by the cord and thrown off the cord as thelatter passes over the pulley.

The humidified air flow will be cooled by evaporation, and may be usedwithout further treatment. The air flow may however be heated ifdesired. If it is desired to have an air flow which is cooled but nothumidified, the humidifying means may take the form of a large-areamember having water-conducting fibres on one side but being imperviousat the other side, and means may be provided to set up a second flow ofair against said other over it, moisture to it.

Important subsidiary features of the invention relates to thearrangement of the fan and large area humidifying means within a housingof relatively thin slab-like orm.

Further features and advantages of the invention will description ofvarious embodiments thereof given by way of example with reference tothe accompanying drawings, in which:

FIGURE 1 is a vertical sectional view of a first form of air humidifierhaving a cross flow fan with a vertical rotor;

FIGURE 2 is a horizontal section of the air humidifier of FIGURE 1,taken on the line IIII of that figure and showing at I-I the sectionline of FIGURE 1;

FIGURES 3 and 4 are vertical sectional views of the second form of airhumidifier having a cross flow fan with a horizontal rotor, the sectionsbeing taken transverse to the rotor axis;

FIGURE 5 is a vertical sectional view of the apparatus of FIGURES 3 and4 taken longitudinally of the rotor on the line VV of FIGURE 3, FIGURE 5showing also at III-III and IVIV the section lines for FIG- URES 3 and4;

FIGURES 6 and 7 are vertical sectional views of a third form ofapparatus wherein a first air flow effects cooling of a humidifyingmember by evaporation and a second air flow is cooled by said memberwithout picking up moisture therefrom both flows being produced by crossflow fans having parallel rotors, the sections being taken transverse tothe axes of the fan rotors;

FIGURE 8 is a sectional plan view of the apparatus of FIGURES 6 and 7,taken on the line VIII-VIII in FIGURE 6 and showing at VI-VI and VIIVIIthe section lines of FIGURES 6 and 7;

FIGURE 9 is a sectional view of a humidifying member in the apparatus ofFIGURES 6 to 8;

FIGURE 10 is an enlarged section of a portion of the humidifying member;

FIGURE 11 is a diagrammatic perspective view of the humidifying member;and

FIGURE 12 is a vertical sectional view of a form of air humidifiersimilar to that shown in FIGURE Referring to FIGURES 1 and 2 of thedrawings, the air humidifier there shown comprises a housing designatedgenerally 1 and having a base 2, a top 3 and spaced side walls 4, 5extending vertically between the base and the top and defining an inlet6 and an outlet 7. A long bladed cylindrical rotor 8 is mounted forrotation about a vertical axis by means of bearings 9, 10 in the top 3and base 2 respectively. A motor 11 within the base directly drives therotor so as to rotate it in the direction indicated by the arrow 12. Thehousing side walls 4, 5 carry guide walls 13, 14 extending inwardlytowards the rotor 8 and co-operating therewith as will be describedbelow. The side walls 4, 5 and guide walls 13, 14 define within thehousing an entry region 15 and a discharge region 16. In the dischargeregion 16 there may be provided an electric heater element as showndiagrammatically at 17. Humidifying means are provided comprising aplurality of vertically suspended wire coils 18 extending between thetop 3 of the housing and the base 2, and communicating with absorbentpads 19, 20 in top and base. A water tank 21 is provided within the base2 and a pump 22 is located therein which causes a small flow of water upa pipe 23 to a header tank 24 in the top 3 of the housing whichcommunicates with the pad 19 therein. The pump 22 may comprise a smallelectric heater (not shown) which produces water-entrainin-g bubbles. Inoperation water flows in a closed circuit from the tank 21 in the base,up pipe 23 to the header tank 24: water flows thence to the pad 19 anddown the wire coils 18 in the form of a film and is collected in the pad20 from which it falls into the tank 21.

The rotor 8 comprises a series of similar forwardly curvedlongitudinally extending blades arranged in a ring, supported on endclosure discs 31-, the blades define an interior space 32 clear ofguides or obstructions. The guide walls 13, 14 have portions 32, 33which guide flow in the entry region 15 to the rotor. The entry guidewall portions 32, 33 merge with discharge guide portions 34, 35respectively at rounded noses 36, 37 which lie on opposite sides of therotor 8 and are well spaced therefrom, preferably by at least half theradial depth of the blades. The discharge guide portion 34 is turnedsharply away from the rotor 8, while the portion 35 diverges graduallytherefrom to merge with the inner surface of the housing wall 5.

On rotation of the rotor 8 a vortex having a core region designated bythe line V and approximating a Rankine vortex is formed wherein the coreis positioned eccentrically with respect to the rotor axis andinterpenetrating the path of the rotating blades of the rotor. The wholethroughput of the machine will then flow twice through the bladeenvelope in a direction perpendicular to the rotor axis indicated by theflow lines F, MP.

Dust will be filtered from the air entering the rotor past the coils 18while at the same time the air passing through the heater is moistenedto raise the humidity and cooled by evaporation. The heater element 17may be used to heat air leaving the rotor.

The device illustrated in FIGURES 1 and 2, considered as a heater, hasan advantage over conventional heaters in that only filtered air passesover the heated coils. These coils may therefore be heated as much asdesired without danger of combustion of dust particles adhering to thecoils. The heater may be used either as a jet type heater or as aconvector type heater.

Referring now to FIGURES 3 to S, the apparatus there shown comprises ahousing 40' of thin slab-like form having a :base 41, an air inlet 42over the greater part of the front side and define-d by a grille 43, anair outlet 44 at the top defined by a grille 45, and rear and end walls46, 47, 48. Tranverse vertical partition walls 49, define within thehousing a central main compartment 51, aligned with the inlet 42 andoutlet 44 and narrow pump and motor compartments 52, 53 at either end. Abladed cylindrical rotor 54 extends longitudinally through the maincompartment 51 just above the base and is mounted for rotation about ahorizontal axis by having one end mounted on the shaft 56 of a motor 57in the motor compartment 53 and the other carried on a stub shaft 58extending through a bearing 59 in the partition wall 49 and mounting apulley wheel 60 within the pump compartment 52.

Guide means co-operating with the rotor 54 comprise a first and secondwall 61, 62 extending lengthwise of the rotor. The guide wall 61 isdisposed above the rotor, subtends at the axis thereof an arc of lessthan 30 and defines with the outer envelope of the rotor blades a gap 63which, in the present instance converges with the rotor in the directionof rotation indicated by the arrow 64: remote from the rotor the wall 61terminates in an upturned lip 65. The wall 62 commences at a line ofnearest approach to the rotor 54 about diametrally opposite the wall 61,and diverges steadily from the rotor going in the direction of rotation.The guide walls 61, 62 and rotor 54 co-operate in the general mannerdescribed with reference to FIG- URE 2 to set up a vortex of Rankinetype having a core region indicated at V which forms adjacent the guidewall 61, the vortex guiding flow through the rotor along lines indicateddiagrammatically at MF, F, which are strongly curved about the vortexcore. Wall 62 terminates short of the rear housing wall 46, to allow fora small amount of recirculating flow around the lower side of this wallas shown by the arrows 66: this assists in the generation of therequired small static pressure.

Evaporative cooling elements 70, 71 of rectangular form are mounted oneover the inlet 42 inside the grille 43 and the other extending slantwisefrom the wall 61 to adjacent the top of the rear housing wall 46. Theseelements 70, 71 have the form of large-area filters composed principallyof absorbent material, such as wood fibres, and allowing free passage ofair across their rectangular area. An interior wall 72 extends throughthe whole length of the main compartment 51 between the partition walls49, 50 and slantwise from the top of the element 70 down to the guidewall 61, with which it forms a nose 73. The evaporative cooling elements70, 71 define with the interior wall 72 and rear wall 46 respectivelyair circulation spaces 74, 75 which seen in transverse section (FIGURE3) are of narrow triangular form, with the rotor 54 adjacent the loweredge of each element and opposite the apex of the triangle. The interiorwall 72 and element 71 define an outlet space 76 of inverted-triangularform as seen in transverse section, with the apex adjacent the wall 61and the outlet 44 forming the base of the triangle. On rotation of therotor 54 air flow takes place through the inlet 42 and evaporativecooling element 70 to the air circulation space 74, thence through therotor in paths which are strongly curved about the vortex core region Vadjacent the wall 61, into the air circulation space 75, through theevaporative cooling element 71 and thence through the outlet space 76and upwardly through the outlet.

The base 41 of the housing 40 is formed as a water tank 80 extendinginto the pump chamber 52. Within this chamber 52 pulley wheels 81, 82are mounted one at the top of the housing 40 and the other within thetank 80, both pulley wheels being in alignment with the pulley 60 drivenby the motor 57 through the rotor 54 and shaft 58. A fibrouswater-absorbent cord or string 83 is trained over these pulley wheels81, 82 and 6t] and driven by the latter as shown by the arrows so as topick up water from the tank 80 and convey it upwards; a spring-urgedjockey pulley 84 is provided to tension the cord. A splash guard 85around the pulley 81 collects water thrown off by the string as itpasses around the pulley 81, and ducts 86, 87 lead the water todistributing grooves 88, 89 at the top of the evaporative coolingelements 70, 71 and having small holes 90 at intervals along theirlength. The water is soaked up by the fibres of these elements andevaporated ve.g. taken from outside a room an evaporative coolingelement made up of top and plates 115 and a series varea of the frame.This cially FIGURE an and an impervious non-absorbent layer 122 on theother.

' nated paper or fabric to inwards. The second air flow therefrom by theair flow, the tank 80.

The arrangement described provides efiicient humidification andconsequent cooling of the air flow, since it utilizes large-areaevaporative cooling elements through which the air flow is relativelyuniform over their length. By reason of the arrangement of evaporativecooling elements and rotor to form narrow air circulation spaces,effective use is made of the space within the housing which accordinglycan be narrow and compact. The apparatus is self-contained by reason ofthe water tank in the base of the housing and of the pump-inducedcirculation of water therefrom over the evaporative cooling elements.Among possible variations, the pump described could be replaced by aconventional gear pump or other type.

The apparatus of FIGURES 6 to 11 is intended for use when an air flow isto be cooled without humidification thereof atthe same time. In thisapparatus a first air flow, to be cooled, is led over to evaporate waterfrom it and thereby cool it, while a second air flow, e.g. from the roomto be cooled, is led past the element and thereby cooled, thearrangement keeping the two flows separate any surplus falling back intoand preventing the second from taking up moisture.

The apparatus comprises a cubical housing designated generally 100having front and rear walls 101, 102, end walls 103, 104 and a top wall105. The housing 100 is subdivided by transverse vertical partitionwalls 106, 107 into a central main compartment 108 and narrow pump andmotor compartments 109, 110 at either end. An evaporative coolingelement of rectangular outline and designated generally 111 is arrangedslantwise in the main housing compartment top front thereof. The

108 from the bottom rear to the element 111 comprises a frame 112 bottomplates 113, 114 and end of rods 116 extending between the in twoparallel rows. An upper over the top portion of the frame top and bottomplates cover plate 117 extends at the front, and a lower cover plate 118extends over the bottom portion of the frame at the rear. A' sheet-like.member 119 is wound concertina-wise over the rods 116 to form a seriesof pleats 120, and extends over the whole member 119 comprises (seeespeabsorbent layer 121 on one side The layer 122 may be a plastics foilor a sheet of impregwhich is secured a fibrous struc- 121. Alternatinginterspaces 123 120 have the absorbent layer 121 inward-facing. Thefirst air flow passes into these interspaces 123 from the top rear ofthe element 111 and emerge through slots 124 in the bottom plate 114thereof. Alternating interspaces 126 between the pleats 120 of themember 119 have themon-absorbent layer 122 facing passes through theseinterspaces 126 from the bottom front of the element 111 and emergethrough slots 127 in the top plate 113 thereof. The sheet-like member119 lies snug against, the plates 113, 114, 115 of the frame and againstthe cover plates 117,

ture forming the layer between the pleats flowing on opposite sides ofthe sheet like member 119 over substantially its total area.

Referring again to FIGURE 6, in the generally tri- "angular spacesdefined in the main housing compartment 108 by the evaporative coolingelement 111 there are mounted cylindrical bladed rotors 130, 131respectively which extend horizontally parallel and close to theadjacent longitudinal edge of the element, is directly driven by aseparate motor 132, 133 in the motor compartment 110, the direction ofrotation being shown respectively by the arrows 134, 135. Each rotor130, 131 co-operates with guide walls 136, 137 and 138, 139: these wallsare formed in the same general manner as the guide walls described withreference to FIGURE 3 and co-operate with the respective rotor in themanner described with bubbles will form in the tube reference to FIGURES1 and 2, flow being shown by the arrows. The first guide wall of eachpair, 136, and 138, have extensions terminating adjacent the coverplates 118, 117 respectively of the evaporative cooling element 111,while the second guide wall of eachpair 137, 139.terminates at the topand bottom plates 113, 114 respectively of the element.

An inlet 140 and an outlet 141 for the first flow are formed at top andbottom of the rear housing wall 102. The rotor 130 in operation receivesair direct from the inlet; the first air flow then passes through theinterspaces 123 and out through a short duct 142 to the outlet 141.

An air inlet 143 and an air outlet 144 for the second air flow areformed at the bottom and top of the front housing wall 101. The rotor131 in operation receives air through the inlet 143 and passes itthrough the interspaces 126 and thence through a short duct 145 to theoutlet 144.

The space below the rotor 130 is formed as "a water tank 146 and as inthe embodiment of the invention illustrated in FIGURES 3 to 5 a pump inthe form of an endless absorbent cord or string 147 in the pumpcompartment 109 takes water from the tank and supplies it to the fibrousabsorbent layer 121 of the evaporative cooling element 111. The rotor130 drives a pulley wheel 148 which in turn drives the cord 147 around alower pulley wheel 149 in the tank 146 and an upper pulley wheel 150 atthe top of the housing, the cord being tensioned by means of aspring-urged jockey pulley 151. A splash guard 152 about the upperpulley wheel 150 takes water thrown off the cord 147 and leads it to anoutlet pipe 154 extending along the rotor 130 and above it, whence itpasses in the air stream on to the absorbent layer 121 of theevaporative cooling element 111.

It will be appreciated that the first air flow cools the sheet-likemember 119 by evaporation of water from the absorbent layer 121 on oneside thereof: the second air flow is cooled by flowing over thenonabsorbent layer at the other side of the member 119 but does not pickup water from it.

The evaporative cooling element 111 is made to be easily dismantled, forchanging the member 119. The upper plate 113 is slidable within groovesin the side plates 115 of the frame 112, and can be locked in positionby the pin 161. Plate 113 is fitted into the grooves 160 by spreadingthe side plates 115 apart, inserting the plate 113 and then moving theside plates 115 towards each other such that the grooves 160 engage withthe ends of plate 113. One row of rods 116 is secured to the top plate113 and the other to the bottom plate 114.

An alternative pumping means is illustrated in FIGURE 12 for pumpingwater from the tank 80 up to the ducts 86 in a humidifying devicesimilar to that shown in FIG- ,URE 4. The pump means comprises anelectric heating element'170 which extends into the bottom of a tube 171which in turn connects the interior of the tank 80 with the ducts 86. Asthe water within the tube is heated, which will flow upward and carrywater from the tank to the ducts 86.

I claim:

1. An air humidifier comprising a housing having an inlet and an outlet,a bladed cylindrical rotor mounted for rotation in said housing, a motorfor rotating said rotor in a predetermined direction, guide meansco-operating with the rotor whereby on rotation of the rotor to set up aflow of air in a direction perpendicular to the axis of the rotor fromthe inlet through the path of the rotating blades to the interior of therotor and thence again through the path of the rotating blades to theoutlet, and humidifying means extending over the length of the rotor andparallel to the axis thereof, said humidifying means including elementsto carrying water into the path of said flow and means to supply waterto said elements.

2. An air humidifier as claimed in claim 1, wherein the water supplymeans comprises a water tank in said entraining bubbles.

4. An air humidifier as claimed in claim 2, wherein the pump comprisesan endless fibrous cord dipping into the tank and mounted on pulleywheels driven by said motor and including an upper wheel above saidtank, and means associated with the upper pulley wheel to collect waterraised from the tank by the cord and thrown 01f the cord as the latterpasses over the pulley.

5. An air humidifier as claimed in claim 2, wherein said rotor axis isvertical and said water-carrying elements comprise a plurality ofvertically suspended wire coils.

6. An air humidifier as claimed in claim 1, wherein said humidifyingmeans is on the inlet side of the rotor and a heating element is locatedat the outlet side thereof.

7. An air humidifier as claimed in claim 1, wherein the humidifyingmeans comprises a large-area fibrous filter member of rectangularoutline which is readily permeable to air flow through said rectangle,the fibres of said filter member providing said water-conductiveelements.

8. An air humidifier as claimed in claim 7, wherein the rotor is locatedclose to one edge of said rectangle, said housing defining a circulationspace of narrow triangular cross section wherein the rotor is oppositethe apex of the triangle.

9. An air humidifier as claimed in claim 7, wherein the humidifyingmeans comprises a water tank in said housing and a pump to supply Waterfrom the tank to the filter, the pump leading water to a locationupstream of the filter for transport onto the filter in the air flow.

10. An air humidifier as claimed in claim 1, wherein the humidifyingmeans comprises a large-area member of rectangular outline having at oneside fibres providing said water-conductive elements and beingsubstantially impervious to air through said rectangle, and means to setup a second flow of air against the other side of the humidifying memberso as to be cooled thereby due to evaporation of water into the firstflow.

11. Air cooling apparatus comprising a housing having an inlet and anoutlet, an air-permeable evaporative cooling member of rectangular areamounted within the housing and having water conducting fibres over saidarea, means to supply water to said fibres, Wall means defining withsaid member a triangular section air circulation space of small apicalangle, bladed cylindrical rotor means rotatably mounted in saidcirculation space opposite the apex thereof and adjacent and parallel toone edge of the rectangle with said edge and said rotor means being ofsubstantially the same length, a motor to rotate the rotor means inpredetermined direction and guide means cooperating with the rotor meanswhereby on rotation thereof to set up a flow of air from the inletthrough the path of the rotating blades of the rotor means to theinterior thereof and thence again through the path of the rotatingblades to the outlet, said flow taking place traversing said circulationspace and the evaporative cooling member whereby to evaporate watertherefrom and thereby cool said air flow.

12. Apparatus as claimed in claim 11, comprising a second evaporativecooling member of rectangular area within said housing and having waterconductive fibres over said area receiving water from said supply means,second wall means defining with said second cooling member a second aircirculation space of small apical angle,

said first and said second air circulation spaces being side by side insaid housing (as seen in vertical section perpendicular to the rotormeans axis), the rotor means being horizontallymounted at the bottom ofboth spaces and opposite the apex of each and co-operating with theguide means to form a vortex of Rankine type having a core regioneccentric of the rotor axis and above it, said air flow taking placefrom the inlet through one air circulation space and thence through therotor means in a curved path around said vortex core region and throughthe second air circulation space to the outlet.

13. Apparatus as claimed in claim 12, wherein the inlet is at one sideof the housing, the first evaporative cooling member extends thereover,the outlet is at the top of the casing and communicates with atriangular section outlet space which is defined by the wall means ofthe first air circulation space and the second evaporative coolingmemher and which has its apex downward.

14. Air cooling apparatus comprising a housing, a

large-area evaporative cooling member in said housing having arectangular outline and having at one side water conductive fibres andbeing substantially impervious to air flow at the other side, means tosupply water to said fibres, two cylindrical bladed rotor means mountedfor rotation within said housing and being parallel to and adjacentopposite long sides of said evaporative cooling member, motor means torotate the rotor means in predetermined directions, guide means for eachrotor means co-operating therewith on rotation thereof to induce an airflow from an entry side of the respective rotor means through the pathof the rotating blades thereof to the interior thereof and thence againthrough the path of the rotating blades to a discharge side of therotor, said air flows of the respective rotor means being separate andone passing over the fibres of the evaporative cooling member toevaporate water from and thereby cool said member and the other passingover the other side of the member so as to be cooled thereby withoutpicking up any substantial amount of water therefrom.

15. Apparatus according to claim 14, wherein the evaporativecoolingtmember comprises a sheet like element which has a fibroussurface on. said one side and an impervious surface on said other sideand which is supported concertina-wise on a series of spaced parallelrods to form a series of pleats, one of said flows passinglongitudinally through the alternating interspaces formed by said pleatswhich have the fibrous surface facing inward the other flow passinglongitudinally through the alternating interspaces formed by said pleatswhich have the impervious surface facing inward.

16. Apparatus according to claim 15, wherein the evaporative coolingmember is mounted diagonally in the ,housing, the respective flowsentering inlets at opposite sides of the housing and each flow leavingthrough an outlet on the same side as the respective inlet, the outletscommunicating with opposite end edges of the evaporative cooling member.7

References Cited UNITED STATES PATENTS v 1,920,952 8/1933 Anderson 230-2,014,773 9/1935 Matteson L. 26l-2 9 2,778,203 1/1957 Griffith 26l-30 XR2,942,773 6/1960 Eck 230 125 3,035,760 5/1962 Simmons 230-425 3,126,4283/1964 Ash 26129 XR HARRY B. THORNTON, Primary Examiner. R. R. WEAVER,Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent N0 3 ,348,828 October 24 1967 Nikolaus Laing that error appears in the abovenumbered pat- It is hereby certified d that the said Letters Patentshould read as ent requiring correction an corrected below.

In the heading to the printed specification, line 7, after "A 7,305/65"insert Germany, Dec. 31, 1956, L 26,542

Signed and sealed this 25th day of February 1969.

(SEAL) Attest:

EDWARD J. BRENNER Commissioner of Patents Edward M. Fletcher, Jr.

Attesting Officer

1. AN AIR HUMIDIFIER COMPRISING A HOUSING HAVING AN INLET AND AN OUTLET,A BLADED CYLINDRICAL ROTOR MOUNTED FOR ROTATION IN SAID HOUSING, A MOTORFOR ROTATING SAID ROTOR IN A PREDETERMINED DIRECTION, GUIDE MEANSCO-OPERATING WITH THE ROTOR WHEREBY ON ROTATION OF THE ROTOR TO SET UP AFLOW OF AIR IN A DIRECTION PERPENDICULAR TO THE AXIS OF THE ROTOR FROMTHE INLET THROUGH THE PATH OF THE ROTATING BLADES TO THE INTERIOR OF THEROTOR AND THENCE AGAIN THROUGH THE PATH OF THE ROTATION BLADES TO THEOUTLET, AND HUMIDIFYING MEANS EXTENDING OVER THE LENGTH OF THE ROTOR ANDPARALLEL TO THE AXIS THEREOF, SAID HUMIDIFYING MEANS INCLUDING ELEMENTSTO CARRYING WATER INTO THE PATH OF SAID FLOW AND MEANS TO SUPPLY WATERTO SAID ELEMENTS.